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From the impossible to the possible: Magda Streicher--Presidential Address 2008.

When I think back on the past year, sewing as President of ASSA, I cannot help but feel grateful for the wonderful opportunity granted to me to make my small but hopefully valuable contribution to astronomy. Encouraging and promoting astronomy has been one of my highest priorities during my tern, which I hopefully achieved. It was a great pleasure and bonus to travel the country to the various branches and to meet and make new friends. I also would like to thank my fellow councillors for their invaluable support and cooperation during the past year. Om deel vanASSA se familie to wees is 'n voorreg en om as ASSA President 'n bydrae to kon lewer 'n nog groter voorreg. 'n Woord van dank aan my kollegas op die Raad wat samewerking op 'n hoe vlak moontlik gemaak het. Laurie Simone was by uitstek my steunpilaar en altyd daar met sy bystand en ondersteuning.

My goal is always to take on various deep-sky projects, attempting to make the impossible possible with visual observations in my telescope. The key to success is dedication and the bonus is observing skills gained. You might ask why I spend time in the wee hours of the night trying to observe these faint objects? The answer is a straightforward one--my love for astronomy is boundless. I am motivated to look deeper than I ever thought possible. I once said to someone that heaven alone knows why I love the faint fuzzies so much. Like the famous response of a mountaineer, his reply was: "Because they are out there". Let me tell you about a few of the faint and elusive deep-sky objects that I have finally managed to capture.

Observing history of the nebulae around the star, Eta Carinae

Inside NGC 3372, known as the Eta Carinae Nebula, the bright 3.5 magnitude orange Eta Carinae is also surrounded by an orange-red nebula about 15" wide, called the Homunculus, named by Gaviola due to its resemblance to a small, stubby manikin. Detected visually by RT Innes in 1914, it was at first recorded as faint 'companion stars'. This nebula is expanding at 5 000 km/s--this expansion represents as much energy in six seconds as our Sun pumps out in an entire year.

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My first real deep-sky observation of this nebula dates back to 2001 when I noted only two soft lobes embedded in haziness around the star Eta Cannae. On a yearly basis I found that the south-eastern lobe was getting slightly larger and brighter. Follow-up observations indicated dark markings superimposed on this SE lobe. Dark skies and averted vision treated me to a faintly visible flare between the two lobes in 2005. Later observations indicated that Eta Carinae and the whole area around the star seem much brighter and dustier. The smaller NW lobe has probably not changed in size, but it looked even smaller against the swollen SE lobe than it did in my sketch of four years ago.

My latest observation made in December 2007 showed uneven surfaces on both the lobes. Three darker spots in the brighter lobe, one a tad brighter, could be made out. A small bright patch embedded in the smaller NW lobe is visible. Two small dents, or notches, in the larger SE lobe on its NW peripheral rim were a surprise. With averted vision the lovely bladed fan between the two lobes was spotted quite easily.

It is a scientific fact that the nebula has brightened considerably over the past few years. The star varies slightly in brightness with a cycle of 5.52 years, which has been traced back to the 1950s. Maybe a supernova lingers on our doorstep, waiting on the verge of destruction at the very end of a massive star's short life.

Targeted Fuzzies: UGC 2838--Galaxy imbedded in the Pleiades--Taurus

The Pleiades star cluster has been known for thousands of years. But did you know that on its western edge, still lingering in the nebulosity, is a faint galaxy (UGC 2838) keeping this cluster company, although it is much more distant. Star hopping is the best way to find these incredibly faint objects. Starting at the 3.6 magnitude Electra in the NW part of the Pleiades star cluster, I hopped over to the 10 magnitude orange-coloured star, GSC 1799 325 1, which is 12' NW from Elects. With a detailed star map the next target star is 11.1 magnitude GSC 1799 721, just 7' to the south.

The area around this star was sketched with high power (346-magnification) to reveal all the faint stars seen in a field of 4 arc minutes diameter. The position of the galaxy, RA: 03h43m38s and DEC: +24[degrees]03'40", is 1' north of this 11.1 magnitude star. Checking over and over again I have come to the conclusion that a faint fuzzy spot more or less at this position could well be the edge-on galaxy UGC 2838, which I estimate around 15.5 magnitude. This observation has been one of my faintest to date.

ESO 172.7, IRAS 12419-5414--Centaurus (RA: 12h41m55s DEC: -54[degrees]14'.9)

This object, catalogued as ESO 172.7, was indicated as "peculiar", before astronomers became aware of its obscure nature. It has been found to be one of the coldest objects in the universe.

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Ian Glass and G Wegner, were the first to note this unusual nebulosity as a 'butterfly or 'bow-tie' in shape, during an inspection of print number 172 from the ESO Quick Blue survey. Blue and visual plates were obtained using the Wynne corrector at the Newtonian focus of the 1.9-m telescope in Sutherland on 16 August 1978. It appears to belong to the class of bipolar nebulae discussed inter alia by Calvert & Cohen (1978). Its dimensions from the blue plate, as measured by Mrs S Parker, are approximately 55 x 21 arc seconds. It is just visible on the Franklin-Adams Atlas plate of the region, taken in 1910. Photometry measured on the Johnson UBV system on the nights of 12, 25 and 26 July 1978 with the 0.5 and 1.0-m reflectors at Sutherland has yielded V= 12.68, B-V= +1.31, U-B= + 1.00. The central star, near spectral type GO 111, is surrounded by a dust shell. This object was named the "Boomerang Nebula" in 1979. Thanks to Ian Glass who provided me with this information.

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It required several attempts for me to observe this small, very faint object. My first impression was of a very faint colourless elongated N-S nebula just about 1' in size. It can only be seen with careful observation, high power and with the use of filters. With filters it resembles two out-of-focus 11 magnitude stars, effectively on top of one another. The double-lobed nebula appears even in brightness, except for a small broken middle area. To observe this unique faint object through my 16-inch telescope brings such a feeling of achievement and joy.

LHA 120-N59c--(M2002) 163282--Nebulae--Dorado

Observing the Large Magellanic Cloud on the evening of 5 August 2005 led me to find a small round patch of nebulosity just 2.7' SE of NGC 2035. All the nebulae in this area were brilliantly enhanced with an UHC filter in the 12-inch telescope at 218x. I could not find any data on this nebular patch, so I forwarded my query to Brian Skiff, a professional astronomer at Lowell Observatory.

His reply was: "The object you have found was catalogued by Karl Henize in 1956 as his 'N59c', or more fully, 'LHA 120-N59c'. It is centred on a 14.5 magnitude star that is obviously the star that fluoresces the circular nebula. The position of the star is: RA:05h35.39.7 and DEC: -67[degrees]37'04".8 (J2000). In the MC catalogue by Phil Massey (who is also at Lowell Observatory), it is called [M2002] 163282. His photometric data are: V = 14.55, B-V = -0.05, U-B = -1.01. The strong negative value for the U-B colour is indicative of a very hot star. Interestingly, the nebula is not drawn-in (sic) on Mati Morel's usually very complete large-scale maps of the Clouds".

So I asked Mati Morel directly. He replied: "Thanks for your interesting note. The region is shown on my chart 23 of 'LMC Selected Areas' but the photo-chart I used as a basis probably did not show Henize N59c (or not very well), so it was ignored. I have looked at a print from UK Schmidt plate and, not surprisingly, N59c shows up very nicely. At least your observation proves that even this small nebula is within reach (visually) under good conditions".

Possible third companion discovered--Aries

When checking the proper motion of all stars, you are bound to get stars of similar proper motion through space. The cluster DoDz 1, in the constellation Aries, contains a double star in its southern extremity, consisting of a yellowish 8.5 magnitude primary and 12.7 magnitude companion with a separation of 29.4", position angle 342[degrees], listed as WDS02474+1713.2. The double star at the position of RA: 02h47m.4--DEC: +17[degrees]13'24" was observed by Tim Cooper and myself on the night of 30 October 2005. To our surprise and after further investigation by Cooper on DS S plates, it showed a possible third companion.

Again I questioned Brian Skiff who noted that it looked as though the faint third star (about) 16 magnitude, situated between the known pair, could possibly be a physical companion. Skiff noted: "The data are not all that good for such a faint star, but the 2MASS colours at least do not totally exclude if'. Hopefully observations of proper motion over time will include or exclude this star as a third companion to WDS02474+1713.2.

Supernova 1987A--Sanduleak--69[degrees]202

I normally shift from NGC 2070 (the Tarantula Nebula), to the small star clusters, NGC 2060 and NGC 2044 further south, from where I star-hop to the position of Supernova 1987A. The titanic supernova explosion was first observed on 23 February 1987. The star, Sanduleak -69[degrees]202, which was 11.7 magnitude prior to outburst, reached naked eye visibility at the time.

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SN 1987A blazed with the power of 100 million suns for several months following its discovery and brightened up more than 2 000 times. Although the supernova itself is now a million times fainter than 20 years ago, light echoes are just beginning to show in the space surrounding it I started to monitor and sketch this area carefully, which shows a very faint elongated NE-SW haze, which I estimate to be around 12" in size.

February 2007 brought a breakthrough. It was a perfectly clear night with excellent seeing conditions and exceptional transparency with a limiting magnitude of 6.3 and the target area high up in the sky. The 12-inch S/C telescope (342x) revealed that this faint elongated haze was broken in two pieces towards the middle. The next step was to measure the size of the gap between the two pieces of the nebulosity, which I estimated around 4" in size. Tim Cooper visited me during November 2007 and our main aim was for him to identify and confirm the gap between the pieces of nebulosity. To my great disappointment, the weather conditions were against us.

Numerous emails were exchanged between Auke and myself, trying to reveal the true identity of the two hazy pieces of nebulosity. DSS plates revealed a short string of very faint stars situated very close to one another, barely 5" in size, corresponding well to the slender NW nebulosity seen through my telescope. I now know this to be the unresolved faint string of stars, but what about the other piece of nebulosity?

I used cross-hairs to pinpoint the correct positions of stars down to magnitude 15.5 around the area as accurately as possible. Two faint stars, one on the NW, the other on the SE rims of the remnant were embedded in the possible nebulosity at the position of RA: 05h35m28.065s--DEC: -69[degrees]16'10.7". We came to the conclusion that the unidentified piece of nebulosity might well be the area surrounding the site of the supernova.

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Earlier this year, I asked Christopher Middleton to provide me with a CCD picture of this area using his 12-inch S/C telescope and Starlight Xpress SXV H9C camera. The two pieces showed up clearly in his picture of 19 February 2008, which confirmed my observation, despite the electronic noise in the picture.

In conclusion, where do I stand now in my desperate search for the first traces of the light echo, the so-called circular reflection around SN 1987A? I really do not know but hopefully I will one day be able to exclaim: 'I have seen it'!

A wise old astronomer once said, if you are not outside looking, you will only read about it I decided to rather be out there!
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Title Annotation:annual general meeting; Astronomical Society of Southern Africa
Publication:Monthly Notes of the Astronomical Society of Southern Africa
Article Type:Speech
Geographic Code:6SOUT
Date:Dec 1, 2008
Words:2180
Previous Article:Two new telescopes commissioned in Sutherland.
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